Yasa channeled electric currents throughout his body to strengthen his flesh. Not only did this not waste his energy, but it left him feeling refreshed and invigorated, as if he could shatter anything with a single punch.
After filling his empty stomach with a full-course meal, Yasa was astounded by the sheer quantity of food he'd consumed.
He quickly understood, however. A powerful physique and potent Devil Fruit ability would naturally require massive energy consumption. In the future, he might even eat an entire mountain without batting an eye.
"Humans can only replenish energy through food," Yasa mused. "The stronger you are, the more you'll burn!" He shrugged it off.
The Pirate World might lack many things, but it's rich in high-energy foods. If necessary, he could always spend some Beli to buy Sea Kings for a snack.
In a remote forest where few humans ventured, among the towering ancient trees, a small log cabin stood near the White White Sea—this was Yasa's current abode.
"One thousand nine hundred ninety-eight, one thousand nine hundred ninety-nine, two thousand!"
Beside the cabin, on a rough-hewn wooden board split from a thick branch, Yasa performed push-ups. His upper body was bare, a large log strapped to his back, with only his thumb touching the ground. He strained his arms, waist, and abdomen through this intense exercise.
Sweat streamed down his chiseled muscles, making him glisten as if he'd just bathed.
After completing two thousand push-ups, Yasa showed no sign of stopping. He pushed himself relentlessly, wringing every ounce of potential from his body.
His movements rose and fell with terrifying speed.
His electrode-enhanced physique grew stronger at a pace he could almost feel. To prevent this power from becoming uncontrollable, Yasa had to maintain strict control through constant training.
The series of high-intensity exercises he performed, especially the weighted training, would terrify most people.
Yasa found no boredom in this relentless training. He was completely immersed in the joy of gaining strength.
Over this period, his power had grown exponentially. He was now confident that if he encountered the Black Bear Bravel from a year ago, he could kill it with two punches.
Wiping the sweat from his handsome face, Yasa gazed toward Angel Island. His mind made up, he resolved to conquer God's Island Apayado within a month—there he'd have them build his future vessel, the ark "Thunder God."
After completing his push-ups, he moved on to squats, punching relentlessly with every ounce of strength. He wouldn't rest until his muscles burned.
His ambition was to become the most free-spirited man on the sea, unbound by any rules. To achieve this, strength was the foundation.
To live a life of excitement and happiness, he knew he'd inevitably make others unhappy.
By morning's end, having completed his training, Yasa sighed in satisfaction. He began preparing lunch, his days filled with purpose.
"Morning training to control my explosive strength. Afternoon developing my Devil Fruit ability. Nighttime sleep with electrodes to strengthen my body!"
He'd laid out his path clearly. With unwavering dedication, he'd soon possess the power to roam the seas freely.
Wiping his sweat, Yasa scooped a ladleful of water and splashed it over his body, washing away the stench of exertion.
Devil Fruit users feared seawater, but ordinary water posed no threat. Otherwise, how could they bathe? (Don't argue yet—the Strongest Enemy Z arc proves it. The Straw Hat crew and Aokiji bathed in hot springs without issue.)
Yasa deliberately exposed his body to the sea's wash, though he couldn't eliminate the Devil Fruit's weakness to saltwater. At least this way, he could endure a few extra seconds in the ocean.
Aokiji could plunge his hand into the sea and freeze the water, proving he'd temporarily overcome his weakness to seawater.
Back in the log cabin, Yasa devoured the prepared food to restore his strength. Then he transformed into a streak of lightning and flew to the White White Sea's skies, beginning to develop his Devil Fruit ability.
The Rumble-Rumble Fruit's destructive power was terrifying. He didn't want to accidentally blow up Birka and lose the Ark Maxim's blueprints.
Far from Birka, Yasa floated in the clouds. He spread his arms wide to relax, then focused his gaze as lightning began gathering around him.
Zzzt! Zzzt! Zzzt!
Powerful currents roared. His entire body became a lightning element, emitting blinding light. Arcs of electricity danced like lightning serpents around him, their heat making the air shimmer.
"Ten million volts! Thunderbird!"
Controlling the dancing lightning, Yasa pushed forward with both hands. With a low shout, he condensed the dazzling light into a massive Thunderbird.
Caw...
The Thunderbird, forged from gathered lightning, roared like a living creature. Blue electricity crackled across its body as it sliced through clouds and mist with wings sharp as blades.
Boom!!!
Yasa commanded the Thunderbird to strike the White White Sea. Mist and spray erupted as the lightning decomposed countless tons of water. The destructive power dwarfed even his earlier lightning balls.
Though expecting this, Yasa still recoiled from the terrifying display.
Bug-like power. How did Enel develop this only to be defeated by Luffy?
This question defied logic. Perhaps the answer would only come when Luffy set sail in twenty years.
The massive crater beneath his feet still reverberated. Through Observation Haki, Yasa sensed the turbulent air currents below—the Island Cloud, over ten meters thick, had been pierced once more.
His Ten Million Volt Thunderbird proved more lethal than Enel's Thirty Million Volt Thunder Beast. By meticulously controlling the current, Yasa enhanced the attack's destructive potential.
At the Thunderbird's wingtips, he directed the lightning to flow irregularly. This chaotic pattern amplified the blade-like edge, ensuring any obstacle would be sliced apart with terrifying efficiency.
For ordinary flesh and blood, unless they're a freak like Kaido, encountering such cutting power means only one fate—being sliced into meat chunks.
Yasa's Observation Haki range, enhanced by electromagnetic waves, now spans an astonishing five kilometers. Within this radius, he can summon lightning at will, directing it precisely where he desires, without fail.
The Rumble-Rumble Fruit's power is truly formidable, offering near-perfect versatility with no blind spots.
Whether in destructive force, mobility speed, or detection capabilities, it ranks among the top-tier Devil Fruit abilities. Yasa feels immense relief that his gamble paid off.
Moreover, through his development, the gap between him and Enel is now as vast as the heavens and earth. The Rumble-Rumble Fruit in Enel's hands could only be described as a "pearl cast into darkness."
While Yasa currently can't match Enel's habit of unleashing two hundred million volt attacks at will, he's confident he'll reach and surpass that level eventually. Having obtained the ability recently, it's unrealistic to expect immediate mastery.
However, with Enel's development as a reference, Yasa can first replicate all the abilities Enel unlocked. Then, leveraging his modern technological knowledge, he can create even more powerful techniques.